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<li><p>数组名称为<strong>指针常量</strong>。设<code>a</code>为数组名，则<code>a++</code>为非法表达式，报错为<code>++需要左值</code>。</p>
</li>
<li><p>指针变量在32位系统中占<strong>4个字节</strong>，在64位系统中占<strong>8个字节</strong>。</p>
</li>
<li><p><strong>内存对齐</strong>。<code>#pragma pack(n)</code>可改变对齐系数。<strong>有效对其值</strong>是给定值<code>#pragma pack(n)</code>和结构体中最长数据类型长度中较小的那个。有效对齐值也叫<strong>对齐单位</strong>。</p>
</li>
<li><p>字的大小：字的大小取决于处理器的位数，如果是16位机器，则是2字节。如果是32位机器，则是4字节。</p>
</li>
<li><p><strong>赋值兼容规则</strong>是指派生类对象可以当做基类对象来使用，只要存在继承关系即可。</p>
</li>
<li><p><strong>数据封装</strong>是将一组数据和与这组数据有关的操作组装在一起。</p>
</li>
<li><p><strong>this指针</strong>保证每个对象有自己的数据成员，但共享处理这些数据成员的代码。</p>
</li>
<li><p>使用<strong>地址</strong>作为实参传给形参，则实参和形参是同一对象。使用<strong>数值</strong>作为实参，形参则是实参的备份。</p>
</li>
<li><p>结构体中可以定义操作函数，如</p>
<figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">struct</span> <span class="title class_">MyStruct</span></span><br><span class="line">&#123;</span><br><span class="line">	<span class="type">int</span> a = <span class="number">0</span>;</span><br><span class="line">	<span class="function"><span class="type">void</span> <span class="title">output</span><span class="params">()</span> </span>&#123;</span><br><span class="line">		cout &lt;&lt; a &lt;&lt; endl;</span><br><span class="line">	&#125;</span><br><span class="line">&#125;;</span><br></pre></td></tr></table></figure>
</li>
<li><p>定义类的动态对象数组时，系统只能够自动调用该类的<strong>无参</strong>构造函数对其初始化。</p>
</li>
<li><p>对赋值运算符重载时，应申明为<strong>类成员函数</strong>。</p>
</li>
<li><p>A中声明B是它的友元函数，则B可访问A内的成员变量。</p>
</li>
<li><p>new和delete的使用方法：</p>
<figure class="highlight plaintext"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line">//申请与删除数组</span><br><span class="line">int* arr = new int[10];</span><br><span class="line">delete[] arr;</span><br><span class="line">//申请并初始化变量为1与删除单个变量</span><br><span class="line">int * a = new int(1);</span><br><span class="line">delete a;</span><br></pre></td></tr></table></figure>
</li>
<li><p><code>=</code>赋值运算符返回值为等号右边的值，如以下代码:</p>
<figure class="highlight plaintext"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">a=(b=c)+(c=d);</span><br></pre></td></tr></table></figure>

<p>结果a应为c+d的值。</p>
</li>
<li><p>C++中静态多态性为编译时的多态性，动态多态性为运行时的多态性。静态多态性可以由函数重载等实现，动态多态性可以由虚函数实现。</p>
</li>
<li><p><strong>在类内部不能对数据成员直接赋值。</strong>但在C++11中已经支持这么写了。</p>
<figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">class</span> <span class="title class_">Student</span></span><br><span class="line">&#123;</span><br><span class="line"><span class="keyword">public</span>:</span><br><span class="line">	<span class="built_in">Student</span>();</span><br><span class="line">	~<span class="built_in">Student</span>();</span><br><span class="line"></span><br><span class="line">	<span class="function"><span class="type">void</span> <span class="title">getname</span><span class="params">()</span> </span>&#123;</span><br><span class="line">		cout &lt;&lt; name &lt;&lt; endl;</span><br><span class="line">	&#125;</span><br><span class="line"></span><br><span class="line"><span class="keyword">private</span>:</span><br><span class="line">	string name = <span class="string">&quot;Superman&quot;</span>;</span><br><span class="line">	<span class="type">int</span> a = <span class="number">1</span>;</span><br><span class="line">&#125;;</span><br></pre></td></tr></table></figure>
</li>
<li><p><strong>带有纯虚函数的类是抽象类，不能被实例化</strong>。详见：<a target="_blank" rel="noopener" href="https://beyond886.gitee.io/2023/02/07/%E8%99%9A%E5%87%BD%E6%95%B0/?highlight=%E6%8A%BD%E8%B1%A1">虚函数</a></p>
</li>
<li><p>类的静态成员变量的生命周期为程序运行的整个周期，该类的所有对象共用这个静态成员变量。</p>
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